摘要
拮抗链霉菌(Steptomyces spp.)R15菌株是从大白菜植株根际土壤分离得到的,其代谢产生的抗菌物质对多种植物病原真菌有很强的抑制作用。采用ABP选择性培养基诱导培养法,获得4株(R8,R15,R31和AS)产β-1,3-葡聚糖酶菌株。其中链霉菌R15菌株在ABP平板上培养7 d后,透明圈最大(>12 mm),澄清度最高。从R15菌株提取酶液,经10%￣75%的硫酸铵沉淀盐析、羟基磷灰石柱层析及DEAE-52柱层析得到纯化,纯化倍数为13.98,回收率达4.031%。经SDS-聚丙烯酰胺凝胶电泳测得该酶的分子量为41.3 kDa。酶特性研究结果表明,该酶作用的最适温度为55℃,最适pH为5.0,低于55℃、pH 7.5以下酶较稳定。Fe3+、K+、Cu2+、Hg2+对酶有抑制作用,而Ca2+、Fe2+、Ba2+、Mn2+、Al3+及Zn2+对酶有激活作用。
Antagonistic substances which were strong antagonistic to various plant pathology fungi could be produced by Streptomyces spp. R15 strain screened from the rhizosphere soil of Chinese cabbage. Four strains （R8, R15, R31 and AS） which could produce β-1,3-glucanase were obtained by using ABP culture induction. Clearing zones produced by the strain Rl5 were the biggest and clearest （Diameter〉12 mm） after culturing 7 d. The β-1,3-glucanase of R15 was separated and purified by fractional precipitation with （NH4）2SO4 of 10%-75%, hydroxyapatite chromatography and DEAE-52 chromatography. Purification folds and yield were 13.98 and 4.031%, respectively. The molecular mass of this enzyme was estimated to be 41.3kDa by 12% SDS-PAGE. The optimum pH for the enzyme activity was 5.5 and the optimum temperature was 55 ℃, the β-1,3-glucanase was more stable when temperature was lower than 55 ℃ and pH smaller than 7.5. Fe^3＋, K^＋~, Cu^2＋ and Hg^2＋ could inhibit the enzyme activity, while Ca^2＋, Fe^2＋, Ba^2＋, Mn^2＋, Al^3＋ and Zn^2＋ could stimulate the activity.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2006年第5期1266-1270,共5页
Journal of Agro-Environment Science
基金
山东省教育厅科技计划项目(J98B01)
